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author | Tejun Heo <tj@kernel.org> | 2009-07-04 08:10:59 +0900 |
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committer | Tejun Heo <tj@kernel.org> | 2009-07-04 08:10:59 +0900 |
commit | 8c4bfc6e8801616ab2e01c38140b2159b388d2ff (patch) | |
tree | e29e8bbfae362362554b870371a6187b41f92d82 /arch | |
parent | 8f05a6a65d944f2fed4eb384fb58aa8c8e5a9bab (diff) | |
download | op-kernel-dev-8c4bfc6e8801616ab2e01c38140b2159b388d2ff.zip op-kernel-dev-8c4bfc6e8801616ab2e01c38140b2159b388d2ff.tar.gz |
x86,percpu: generalize lpage first chunk allocator
Generalize and move x86 setup_pcpu_lpage() into
pcpu_lpage_first_chunk(). setup_pcpu_lpage() now is a simple wrapper
around the generalized version. Other than taking size parameters and
using arch supplied callbacks to allocate/free/map memory,
pcpu_lpage_first_chunk() is identical to the original implementation.
This simplifies arch code and will help converting more archs to
dynamic percpu allocator.
While at it, factor out pcpu_calc_fc_sizes() which is common to
pcpu_embed_first_chunk() and pcpu_lpage_first_chunk().
[ Impact: code reorganization and generalization ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/include/asm/percpu.h | 9 | ||||
-rw-r--r-- | arch/x86/kernel/setup_percpu.c | 169 | ||||
-rw-r--r-- | arch/x86/mm/pageattr.c | 1 |
3 files changed, 12 insertions, 167 deletions
diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h index 103f1dd..a18c038 100644 --- a/arch/x86/include/asm/percpu.h +++ b/arch/x86/include/asm/percpu.h @@ -156,15 +156,6 @@ do { \ /* We can use this directly for local CPU (faster). */ DECLARE_PER_CPU(unsigned long, this_cpu_off); -#ifdef CONFIG_NEED_MULTIPLE_NODES -void *pcpu_lpage_remapped(void *kaddr); -#else -static inline void *pcpu_lpage_remapped(void *kaddr) -{ - return NULL; -} -#endif - #endif /* !__ASSEMBLY__ */ #ifdef CONFIG_SMP diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index ab896b3..4f2e0ac 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -137,44 +137,21 @@ static void __init pcpu_fc_free(void *ptr, size_t size) } /* - * Large page remap allocator - * - * This allocator uses PMD page as unit. A PMD page is allocated for - * each cpu and each is remapped into vmalloc area using PMD mapping. - * As PMD page is quite large, only part of it is used for the first - * chunk. Unused part is returned to the bootmem allocator. - * - * So, the PMD pages are mapped twice - once to the physical mapping - * and to the vmalloc area for the first percpu chunk. The double - * mapping does add one more PMD TLB entry pressure but still is much - * better than only using 4k mappings while still being NUMA friendly. + * Large page remapping allocator */ #ifdef CONFIG_NEED_MULTIPLE_NODES -struct pcpul_ent { - unsigned int cpu; - void *ptr; -}; - -static size_t pcpul_size; -static struct pcpul_ent *pcpul_map; -static struct vm_struct pcpul_vm; - -static struct page * __init pcpul_get_page(unsigned int cpu, int pageno) +static void __init pcpul_map(void *ptr, size_t size, void *addr) { - size_t off = (size_t)pageno << PAGE_SHIFT; + pmd_t *pmd, pmd_v; - if (off >= pcpul_size) - return NULL; - - return virt_to_page(pcpul_map[cpu].ptr + off); + pmd = populate_extra_pmd((unsigned long)addr); + pmd_v = pfn_pmd(page_to_pfn(virt_to_page(ptr)), PAGE_KERNEL_LARGE); + set_pmd(pmd, pmd_v); } static ssize_t __init setup_pcpu_lpage(size_t static_size, bool chosen) { - size_t map_size, dyn_size; - unsigned int cpu; - int i, j; - ssize_t ret; + size_t reserve = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE; if (!chosen) { size_t vm_size = VMALLOC_END - VMALLOC_START; @@ -198,134 +175,10 @@ static ssize_t __init setup_pcpu_lpage(size_t static_size, bool chosen) return -EINVAL; } - /* - * Currently supports only single page. Supporting multiple - * pages won't be too difficult if it ever becomes necessary. - */ - pcpul_size = PFN_ALIGN(static_size + PERCPU_MODULE_RESERVE + - PERCPU_DYNAMIC_RESERVE); - if (pcpul_size > PMD_SIZE) { - pr_warning("PERCPU: static data is larger than large page, " - "can't use large page\n"); - return -EINVAL; - } - dyn_size = pcpul_size - static_size - PERCPU_FIRST_CHUNK_RESERVE; - - /* allocate pointer array and alloc large pages */ - map_size = PFN_ALIGN(num_possible_cpus() * sizeof(pcpul_map[0])); - pcpul_map = alloc_bootmem(map_size); - - for_each_possible_cpu(cpu) { - pcpul_map[cpu].cpu = cpu; - pcpul_map[cpu].ptr = pcpu_alloc_bootmem(cpu, PMD_SIZE, - PMD_SIZE); - if (!pcpul_map[cpu].ptr) { - pr_warning("PERCPU: failed to allocate large page " - "for cpu%u\n", cpu); - goto enomem; - } - - /* - * Only use pcpul_size bytes and give back the rest. - * - * Ingo: The 2MB up-rounding bootmem is needed to make - * sure the partial 2MB page is still fully RAM - it's - * not well-specified to have a PAT-incompatible area - * (unmapped RAM, device memory, etc.) in that hole. - */ - free_bootmem(__pa(pcpul_map[cpu].ptr + pcpul_size), - PMD_SIZE - pcpul_size); - - memcpy(pcpul_map[cpu].ptr, __per_cpu_load, static_size); - } - - /* allocate address and map */ - pcpul_vm.flags = VM_ALLOC; - pcpul_vm.size = num_possible_cpus() * PMD_SIZE; - vm_area_register_early(&pcpul_vm, PMD_SIZE); - - for_each_possible_cpu(cpu) { - pmd_t *pmd, pmd_v; - - pmd = populate_extra_pmd((unsigned long)pcpul_vm.addr + - cpu * PMD_SIZE); - pmd_v = pfn_pmd(page_to_pfn(virt_to_page(pcpul_map[cpu].ptr)), - PAGE_KERNEL_LARGE); - set_pmd(pmd, pmd_v); - } - - /* we're ready, commit */ - pr_info("PERCPU: Remapped at %p with large pages, static data " - "%zu bytes\n", pcpul_vm.addr, static_size); - - ret = pcpu_setup_first_chunk(pcpul_get_page, static_size, - PERCPU_FIRST_CHUNK_RESERVE, dyn_size, - PMD_SIZE, pcpul_vm.addr, NULL); - - /* sort pcpul_map array for pcpu_lpage_remapped() */ - for (i = 0; i < num_possible_cpus() - 1; i++) - for (j = i + 1; j < num_possible_cpus(); j++) - if (pcpul_map[i].ptr > pcpul_map[j].ptr) { - struct pcpul_ent tmp = pcpul_map[i]; - pcpul_map[i] = pcpul_map[j]; - pcpul_map[j] = tmp; - } - - return ret; - -enomem: - for_each_possible_cpu(cpu) - if (pcpul_map[cpu].ptr) - free_bootmem(__pa(pcpul_map[cpu].ptr), pcpul_size); - free_bootmem(__pa(pcpul_map), map_size); - return -ENOMEM; -} - -/** - * pcpu_lpage_remapped - determine whether a kaddr is in pcpul recycled area - * @kaddr: the kernel address in question - * - * Determine whether @kaddr falls in the pcpul recycled area. This is - * used by pageattr to detect VM aliases and break up the pcpu PMD - * mapping such that the same physical page is not mapped under - * different attributes. - * - * The recycled area is always at the tail of a partially used PMD - * page. - * - * RETURNS: - * Address of corresponding remapped pcpu address if match is found; - * otherwise, NULL. - */ -void *pcpu_lpage_remapped(void *kaddr) -{ - void *pmd_addr = (void *)((unsigned long)kaddr & PMD_MASK); - unsigned long offset = (unsigned long)kaddr & ~PMD_MASK; - int left = 0, right = num_possible_cpus() - 1; - int pos; - - /* pcpul in use at all? */ - if (!pcpul_map) - return NULL; - - /* okay, perform binary search */ - while (left <= right) { - pos = (left + right) / 2; - - if (pcpul_map[pos].ptr < pmd_addr) - left = pos + 1; - else if (pcpul_map[pos].ptr > pmd_addr) - right = pos - 1; - else { - /* it shouldn't be in the area for the first chunk */ - WARN_ON(offset < pcpul_size); - - return pcpul_vm.addr + - pcpul_map[pos].cpu * PMD_SIZE + offset; - } - } - - return NULL; + return pcpu_lpage_first_chunk(static_size, PERCPU_FIRST_CHUNK_RESERVE, + reserve - PERCPU_FIRST_CHUNK_RESERVE, + PMD_SIZE, + pcpu_fc_alloc, pcpu_fc_free, pcpul_map); } #else static ssize_t __init setup_pcpu_lpage(size_t static_size, bool chosen) diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 1b734d7..c106f78 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -12,6 +12,7 @@ #include <linux/seq_file.h> #include <linux/debugfs.h> #include <linux/pfn.h> +#include <linux/percpu.h> #include <asm/e820.h> #include <asm/processor.h> |